1. Field of the Invention
This invention relates to a method of and system for image processing for correcting predetermined image quality of images forming an image group, and a computer program for the image processing.
2. Description of the Related Art
Recently, digital images (will be simply referred to as “an image”, hereinbelow) such as those obtained by photoelectrically reading a picture recorded on a photographic film such as negative film or color reversal film by a reading system such as a scanner or those obtained by taking an image with a digital still camera (DSC) are displayed or printed after correction of image quality thereof, such as brightness, contrast, or white balance. When the image quality is corrected, for instance, when the brightness is corrected, the correction is generally made on the basis of the average brightness of the image before the correction. Accordingly, even images representing continuous scenes or similar scenes such as those in which the objects or the backgrounds are the same can be differently finished when the taking conditions are slightly different. Further, for instance, when graduation albums are to be prepared, portraits of alumni are printed after correction in their qualities. In this case, when each of the portraits looks differently by the quality correction, a sense of incompatibility can be provided to a viewer on the whole. Accordingly, it is desired that the portraits after correction are uniform in brightness, contrast, white balance or the like.
In order to unify the images after correction of the quality, there has been proposed in Japanese Unexamined Patent Publication No. 2002-171408 a method in which the user is caused to designate a reference corrected image out of a plurality of corrected images and the corrected images other than the designated reference corrected image are further corrected to conform to the designated reference corrected image so that the corrected images in an image group have a uniform image quality. By this, since each of the corrected images is corrected to have an image quality equal to the designated reference corrected image, corrected images can have uniform image qualities.
However, the method disclosed in Japanese Unexamined Patent Publication No. 2002-171408 is disadvantageous in that it involves a problem that the image quality of each of the images can deteriorate if a wrong reference image is designated though the images can be unified in the image quality since it is difficult to designate an adequate image as the reference image unless a skilled user, in addition to a problem that it takes long time since it requires designation of the reference image by the user.